Docstoc

choietal4

Document Sample
choietal4 Powered By Docstoc
					The Inhibitory Role of the MA
An example from Choi, G. B., H. W. Dong, et al. (2005). "Lhx6 delineates a pathway mediating innate reproductive behaviors from the amygdala to the hypothalamus." Neuron 46(4): 647-60.

A Model of MA Inhibition
MeA 1
OB MPOA

/ vBST

/
AOB

LSv MeA 2

AHN PMd VMN

PAG

from Numan & Insel 2003

Olfactory Inhibiton
Fleming, A., F. Vaccarino, et al. (1979).
"Vomeronasal and olfactory system modulation of maternal behavior in the rat." Science 203(4378): 372-4.

Fleming, A., F. Vaccarino, et al. (1979).
 Partial reduction in maternal behavior latencies
 Vomeronasal nerve cuts  Olfactory bulb cuts
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

 Large reduction in maternal behavior latencies
 VN +  VN-OB

Olfactory Inhibition
Del Cerro, M. C., M. A. Izquierdo, et al. (1991).
 "Bilateral lesions of the bed nucleus of the accessory olfactory tract facilitate maternal behavior in virgin female rats." Physiol Behav 50(1): 67-71.

Lesions of the BAOT result in lowered maternal behavior latencies

MeA Inhibition
Fleming, A. S., F. Vaccarino, et al. (1980).
"Amygdaloid inhibition of maternal behavior in the nulliparous female rat." Physiol Behav 25(5): 731-43.

Fleming et al. 1980
AM lesions
AM = 2.87 vs. Control = 8.83

AM sub-lesions
Anterolateral cortical nuclei
 Main olfactory input

Medial posteromedial cortical nucleus
 Accessory olfactory input

Lateral & basolateral nuclei
 No olfactory input

Inhibition is primarily mediated by the corticomedial rather than the basolateral portion of the AM

MeA Inhibition
Numan, M., M. J. Numan, et al. (1993).
 "Excitotoxic amino acid injections into the medial amygdala facilitate maternal behavior in virgin female rats." Horm Behav 27(1): 56-81.

Numan et al. 1993
Used NMDA lesions of the MeA
Lowered maternal behavior latencies in experimental vs. control
.5 vs 6 days

MeA is Inhibition
Sheehan, T., M. Paul, et al. (2001).
"Evidence that the medial amygdala projects to the anterior/ventromedial hypothalamic nuclei to inhibit maternal behavior in rats." Neuroscience 106(2): 341-56.

Sheehan, T., M. Paul, et al. (2001).
Bilateral lesions of the MA or AHN/VMN
Promote maternal behavior Higher cFos in MA pup vs. no pup groups
Interhemispheric differences of interest
 AHN  BSTpr  BSTv  LSv  MPOA  PMd  VMNvl

VMH/AHA Inhibition
Bridges, R. S., P. E. Mann, et al. (1999).
"Hypothalamic involvement in the regulation of maternal behaviour in the rat: inhibitory roles for the ventromedial hypothalamus and the dorsal/anterior hypothalamic areas." J Neuroendocrinol 11(4): 259-66.

Bridges, R. S., P. E. Mann, et al. (1999).
Lesions of the DH/AHA
Rapid onset of maternal behavior Depends on steroid treatment

Lesions of the VMH
Lowered latencies to maternal behavor

VMH/DMH are Inhibitory
Mann, P. E. and J. A. Babb (2004).
"Disinhibition of maternal behavior following neurotoxic lesions of the hypothalamus in primigravid rats." Brain Res 1025(1-2): 51-8.

Mann, P. E. and J. A. Babb (2004).
Lesions of the VMH or DMH
Disinhibit primigravid females

A Model of MA Inhibition
MeA 1
OB MPOA

/ vBST

/
AOB

LSv MeA 2

AHN PMd VMN

PAG

from Numan & Insel 2003

BUT!
What about MA activation in maternal females? Numan, M. and M. J. Numan (1995).
"Importance of pup-related sensory inputs and maternal performance for the expression of Fos-like immunoreactivity in the preoptic area and ventral bed nucleus of the stria terminalis of postpartum rats." Behav Neurosci 109(1): 135-49.

Numan, M. and M. J. Numan (1995)
MA activation
Sham Thelectomy

Maybe MA is also facilitatory

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

A dual role of the MeA in Maternal Behavior?
Most evidence suggests an inhibitory role BUT - some evidence suggests a facilitatory role

A Parallel Study
Choi, G. B., H. W. Dong, et al. (2005).
"Lhx6 delineates a pathway mediating innate reproductive behaviors from the amygdala to the hypothalamus." Neuron 46(4): 647-60.

Contrasting MeA Projections
 Reproductive Subdivision
 MeApd  VMHvl

 Defensive Subdivision
 MeApv  MeAa  AHN  VMHdm

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

Image from Choi et al. 2005

Differing Stimuli Activate Differing MeA subunits
Reproductive Stimuli Defensive Stimuli

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

MeA Subunits are Characterized by Differences in Gene Expression
Lhx6
MeApd MeApv

Lhx9
MeApv

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

Lhx5
MeAav

Recap

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

Lhx6 corresponds to
 Lhx6 PLAP
 VMvl  PMv  MPN  BSTpr

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

Lhx9 corresponds to defensive areas
Lhx9 PLAP Results
VMHdm BSTf AHN

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

Recap
Lhx6 expressing neurons project to reproductive hypothalamic nuclei Lhx9 neurons projects to defensive hypothalamic nuclei

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

QuickTim e™ and a TIFF (Uncompres sed) decom pres s or are needed to s ee this picture.

Retrograde Results

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.


				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:1
posted:10/16/2009
language:English
pages:33